Apparatus for equipping branch lines and the like



l1g- 4, 1942- F. H. MUELLER ETAL 2,291,979

APPARATUS FOR EQUIPPING BRANCH LINES AND THE LIKE A AU@ 4, 1942- F. H MUELLER ETAL 2,291,979

APPARATUS FOR EQUIPPING BRANCH LINES AND THE LIKE Filed July 17. 1940 4 Sheets-Sheet 2 mawwpmw AUS- 4 1942- F. H. MUELLER ETAL 2,291,979

APPARATUS FOR EQUIPPING BRANCH LINES AND THE LIKE Filed July 17, 1940 4 Sheets-Shea? 3 il@l Swann/tm am! i had?, i a l Ima/LA S Aug. 4, 1942. F. H. MUELLER ETAL APPARATUS FOR EQUIPPING BRANCH LINES AND THE LIKE Filed July 17, 1940 4 Sheets-Sheet 4 Patented Aug. 4, 1942 2,291,919 APPARATUS Foa EQUIPPING BRANCH LrNas AND 'rms uur.

Frank H. Mueller and Walter J. Bowan, Decatur,

Ill., assigner: to Mueller Co., Decatur, lll., a corporation' of Illinois Application July 17, 1940, Serial No. 346,052

The present invention relates to tapping machines of the type adapted to cut an opening in a fluid chamber to provide an outlet therefrom, and to thread the cut opening to receive a valve body for controlling ilow through vthe outlet. Such operations are customary, for instance, in attaching lateral or branch line connections to a iluid conduit, for instance, to a water or gas main.

l One of the principal objects of the invention is to provide such a tapping apparatus of simple compact construction and of reduced size. The compactness of the apparatus makes possible its use in coniined spaces, for instance, between closely adjacent walls oi a building or of other construction.

Another object of the invention is to provide such apparatus having separate means for advancing a cutting and tapping bar during the respective cutting and tapping operations. The means for advancing the bar during the cutting operation is relatively rugged, whereas the means for controlling its advance during the tapping operation is oi' liner construction to accurately regulate the formation of the tapped threads to the desired pitch.

Another object of the invention is to provide tapping apparatus with improved means for guiding the cutting bar in accurate alignment at the time when the bit is cutting the opening through the curved wall of the chamber or conduit.

It is also an object o! the invention to improve various features of such a cutting and tapping apparatus, in order to simplify its construction and improve its manner of operation, as set forth below. Y

'Ihe drawings illustrate several forms of cutting and tapping apparatus made in accordance with the invention. it being understood that the constructions shown are susceptible of considerable modiilcation within the range o! the invention:

Figure 1 is a central vertical sectional view of a cutting and tapping apparatus attached to a main, showing the position of the drillingvbar at the time the bit is commencing to cut into the wall of the main.

Figure 2 is a view similar to Figure 1, showing a subsequent condition of the apparatus when the bit is tapping threads in the previously cut opening in the main.

Figure 3 is a vertical sectional view of a portion oi the apparatus, similar to Figures 1 and 2,

(Cl. 77-40l valve body. such as a corporation cock, is being insertedthrough the apparatus toward the previously cut and tapped openingin the main.

Figure 4 is a top plan view oi the apparatus. 5 looking down toward the conduit which is being operated upon.

Figure 5 is a partial vertical sectional view of the apparatus. taken through one side of the chain yoke employed to rigidly attach the apparatus to the main.

Figure 6 is a partial horizontal sectional view taken along the line H of Figure 5.

Figure 7 is a side elevational view oi one of the chain harps as shown in Figure 5.

Figure 8 is an enlarged partial vertical sectional view of the iluid chamber bonnet of the apparatus. showing one manner o! attaching a tool or part to the lower end of the drilling bar.

Figure 9 is a horizontal sectional view taken along the line I-I of Figure 8.

Figure 10 is a partial horizontal sectional view taken. for instance, along the line lI-i of Figure 2, showing a device employed to thread the bonnet onto the iluid chamber oi the apparatus. Figure 11 is a sectional view of the bypass valve of the apparatus taken, for instance, along the line I I-I I of Figure 2.

Figure 12 is a sectional view showing details of the bypass valve, taken along the line i2|2 of Figure 11. i Figure 13 is a side elevational view of a portion of the apparatus. with the bypass valve removed.

Figure 14 is a vertical sectional view oi a modiiled form of the apparatus, showing a different type of flop valve. I

Figure 15 is a horizontal sectional view taken along the line iI-Ii of Figure 14.

Figure 16 is a sectional view taken along the line Il-Il ofFigure 14, illustrating details of construction ot the modified ltype o! ilop valve,

and

Figure 17 is a side elevational view of the modiiied apparatus of Figure 14, with the side cover of the ilop valve chamber removed. and showing a construction of this valve and its actuating parts.

In Figure 1, a curved wall chamber such as a gas or water main is shown at Il. and mounted thereon is the usual malleable iron saddle i! which bears against a gasket Il. The saddle I2 has an opening therethrough. and at the outer end of the opening a counterbore It is formed. which counterbore receives the body Il of the but showing the apparatus in condition when a ilop valve chamber, the lower end of said body A,iournaled in the walls of the body. and having a central squared portion to which the flop valve is secured, so that when the shaft is turned, in the well known manner, the flop valve is moved between open and closed positions. y

The upper end of the flop valve body I8 isk interiorly threaded as at 28 and secured thereto is a cylinder 28 which forms a uid chamber with the op valve body around the opening in the main. The operations required in equipping the conduit I8 with a branch line are performed through this chamber, including the insertion of a corporation cock into the opening cut in the main.y It is a purposegof the invention to so simplify the parts, that the length of the cylinder 28 may be reduced, thus effecting economyin construction and making the apparatus more convenient in use, particularly in confined spaces.

The upper end of the cylinder 28 is closed by a bonnet 38, which bonnet is threaded to the upper end of the cylinder in duid tight engagement therewith, for instance, by means of an appropriate gasket, as shown.

'I'he bonnet has an upwardly extending cylindrical portion 32, through winch an operating bar B is adapted to extend into the fluid chamber, and this upwardly extending portion of the bonnet is constructed to receive the parts which are operated to move the operating bar longitudinally through the apparatus, and to turn said bar, in order to perform the cutting, tapping, and corporation cock inserting operations previously mentioned, and well known inthe art. The longitudinal opening in the bonnet is enlarged adjacent its lower end as at 34 to receive packing which forms a seal around the bar B during its operation. f

A bypass valve P is employed to control communication between the portions of the fluid chamber above and below the flop valve seat to facilitate the tight engagement of said flop valve wits its seat, and the subsequent opening of said valve.

The lower end of the bar B is constructed to removably carry a drilling bit D. The lower end of said bit comprises a cutting portion 38, and its upper endris suitably threaded to provide a tapping portion 38. By means hereinafter described, the operating bar B is moved longitudinally through the fiuid chamber until the end of the bit engages the main I8, and thereafter the bar B is turned so that the bit cuts an opening in the main, longitudinal cutting pressure being suitably applied as hereinafter described. As

.further described hereinafter, when the end oi' the bit D has cut through the Wall of the main., regulated' turning means comes into play to controll the rotation and advance of the bar B so that threads of the desired pitch are tapped in ythe 'previously cut opening in the main, by `thev .y tapping portion 38 of the bit.

The lower end of the bar B has an enlarged holder 48 which removably carries the drill D. suitably secured to the outside of this head is a vguide collar 42, of substantial diametenwhich an accurately machined guiding cylindrical porl tion to receive the guide 42, which also has a cylindrical periphery. The guide 42 engaging the guide cylinder 44 properly maintains the bit'D in accurate alignment during the initial cutting of the opening into the curved wall of the main I8, and prevents side shifting of the bar during this cutting operation. It will be evident .that the accurate cutting of the opening through the wall oi' the main, facilitates the' subsequent andv necessarily more refined thread tapping operation. The above described guide is obviously a simple yet effective expedient, making unnecessary the use of pilot drills or other more com plicated guiding means.

Before the bonnet 88 is positioned on the cylinder 28, a chain collar 48, the details of which will be hereinafter described, is placed over the outside of the cylinder, resting against the upper end of the flop valve body I8. A retaining chain or strap is secured to opposite sides of the collar 48 in a manner hereinafter described, and this chain passes downwardly around the conduit I8 and holds the entire assembly rigidly against the outer wall of said conduit.

'I'he upwardly extending portion 32 of the bonnet 88 is provided with relatively heavy exterior threads 88 for the major portion of its length. These threads receive and coact with similar threads on a feed collar 8l, which collar has suitable operating handles 82 extending therefrom.

The bar B has a shoulder 54 adjacent its upper end, and removably sleeved on the bar against said shoulder is a feed regulating thrust collar 58,-

which may be retained on the bar in any appropriate way, as by means of a locking screw. A yoke 58 of Well known construction is pivotally carried by the said-feed collar 8|, as is well known in the art, and the upper end 88 of said yoke contacts the top of the thrust collar 58 and thereby imparts a downward longitudinal force thereto, and to the bar B, when the feed screw is turned on the threads 88. The upper end 82 of the bar B has fiat sides for the engagement of a wrench employed in the conventional manner to turn the bar B. The upper end 88 of the yoke 88 is substantially U-shaped, as shown in Figure 4, to embrace the bar B when it engagea the thrust collar 88.

The thrust collar 58 has a depending cylindrical sleeve 84 having relatively fine regulated threads 88 thereon, which are intended to engage similar threads 88 of the same pitch on the interior of the extension 32 of the bonnet. 'I'he threads-88 and 88 are of the same pitch'as the threads 38 on the cutting and t'. ping bit D, and are much finer than the threads 58 on the exterior of the :bonnet extension 32.

In the operation of the machine as described above, the flop valve body I8 and the cylinder 28 are secured to the main I8, and tightly held thereon by the well-known chain, opposite ends of which are attached to the chain collar 48. When the apparatus is thus assembled to the main, the operatingbar B is in place, extending into the cylinder 28 and having the proper drilling and tapping bit D secured to the lower collar may be Vmade of metal, rubber or leather.

The opening through the flop valve body I8 is end thereof. The interior of the cylinder 28 and the flop body I8 form a duid-tight fluid chamber. The feed collar 5I is then rotated and moves downwardly along the bonnet extension 32 with the top 88 of the yoke 88 engaging the thrust collar 58 on the bar B. The bar B is thus moved downwardly until the bit D encounters the main il. At this time, the cutting operation is to be commenced, and as longitudinal thrust is applied to the bit D and against the wall of the main il by rotation of the feed screw l, the bar B is turned by a suitable wrench engaging its end 62 and whereupon the lower cutting portion of the bit cuts an opening through the wall of the main Il as shown in Figure 1. It will lbe noted that during this cutting operation, the threads 66 carried by the thrust collar 56 are not in engagement with the threads 88 in the interior of the extension 32 of the bonnet.

As the opening is thus cut through the main, continued rotation of the feed screw 5| brings the tapping portion I8 of the bit into engagement with the opening cut through the main. The apparatus is so designed that, just prior to the engagement of the tapping threads with the previously cut opening, the threads 66 on the thrust collar 66 engage the threads 68 in the bonnet extension 82, so that the tapping threads enter the opening in the main already advancing at the proper rate. As previously pointed out,

, the pitch of these threads is the same as that on the tapping portion 88 of the bit. When these threads engage, the longitudinal feed of bar B is exactly regulated, and yoke 58 is disengaged or swung back from thrust collar 58 as shown in Figure 2. The bar B is turned by a wrench engaging its end 82. Threads of exact pitch desired are thus tapped in the opening through the main, this operation being illustrated in Figure 2. When threads 86 and 88 are in engagement, operation of the feed collar 5I will not be required. The tapping may be performed by simply turning the bar B.

It will be understood that the apparatus is designed to receive bits of various sizes, to cut and thread openings of various sizes, and to insert corporation cocks of different sizes. Furthermore, bits may be used having tapping threads of various pitch, as desired, and bonnets having different corresponding threads may be substituted. The thrust collar 58 with its sleeve 6I is removable from the bar B, so that a different collar having threads 88 of different pitch, corresponding with those of the bit, may be used. When the opening has been cut in the main, any fluid under pressure in the latter escapes through the opening into the interior of the apparatus. For this reason, it is well known in the art to control this fluid with a flop valve,v a type of which is shown at F. At the termination of the tapping operation, the bar B is elevated until the cutting and tapping bit is above the valve seat 18 formed in the flop valve body i8 at the lower end of the guide portion 44 thereof. With the bit thus elevated, the squared shaft 24 may be turned by its handle H to cause the flop valve F to engage its seat. The closed flop valve completes the formation of an outer fluid tight chamber within the cylinder 28, and an inner fluid tight chamber within the body I8. When the flop valve is seated, the bypass valve P is operated, as is well known in the art, to release fluid under pressure from the fluid chamber above the flop valve. The differential pressure thus created on opposite sides'of the op valve causes it to be tightly held against its seat. When so held, the bonnet l0 may be removed from the cylinder 28, and the cutting and tapping bit may then be removed from the bar B. A tool employed in subsequent operations may then be substituted for the blt D, or a valve body or corporation cock may be attached to the lower end of said bar. When'this is done, the apparatus is again assembled with the bonnet tightly engaged on the upper end of the cylinder 2l reforming the pressure chamber, and subsequent operations proceed as hereinafter described.

The upper or outer end of the cutting and tapping bit D is provided with a longitudinal guiding slot 16 to hold it against rotation in the holder l0, the latter being provided with a lug 1B which extends into the slot 18. The lower end of the inner surface of the slot 16 is outwardly curved as at and a knock-out pin l2 having a rounded inner end is mounted extending through the lower wall of the holder 40. A lock screw 84 is also provided to retain the Ibit in place in the holder, as is well known in the art. When the cutting and tapping operations have been completed, and the flop valve has been closed and the bonnet removed, the bit D may be conveniently removed from its wedged engagement in the holder l0, by first releasing the retaining screw 8l, and then, giving the knock-out pin 82 a sharp blow with a hammer. 'I'he inner rounded end of the knockout pin 82 engages against the inner curved cam surface of the lower end of the slot 16, thus applying an outward force to release the bit D from its retained position in the lower end of the holder 40.

The ilop valve F of the present apparatus is of improved construction, as now described, to make more convenient the insertion of such a device as a corporation cock for the previously cut and tapped opening. The design is such that the length of the cylinder 28 may be shorti ened, in turn making possible the shortening of the over-all length of the apparatus and making possible its use in confined places. shortening of the cylinder 28 also reduces the distance the bit or corporation cock must be moved to engage the conduit I8.

Referring to Figures 1, 2 and 3, the flop valve F is shown provided with a substantial well 80 extending downwardly from its upper surface, and surrounding this well is a circular gasket 82 suitably heldin place as by means of small screws. When the flop valve is closed, as shown in Figure 3, the gasket 82 engagesthe valve seat 18 on the flop valve body, thus forming a seal between the flop valve chamber and the chamber formed by the cylinder 28. In Figure 3, the holder I8 on the lower end of the bar B is shown carrying a corporation cock C of well known construction. said cock having a lower end suitably threaded to t in the threads previously tapped in the opening in the main I8. The upper end of this corporation cock is engaged in a tool having a shank formed in a manner similar to the upper end of the bit D, so that it may be carried by the holder and bar B and released therefrom by operation of the same type of knock-out pin.

When the corporation cock is positioned in the chamber formed by the cylinder 28, its lower end extends downwardly into the well 80 of the flop valve F so that a portion of the vertical dimension of the flop valve chamber is used to initially receive the corporation cock when the flop valve is closed. That is, as shown in Figure 3, the lower end of the corporation cock extends a substantial distance below the valve seat l0, although it remains in the outer fluid chamber formed by the cylinder 28. Thus, the length of the cylinder 28 may be reduced.

With the parts in the position shown in Figure 3, the bypass valveP is operated in a manner generally well known in the art to equalize presto pass upwardlyinto the chamber above the' same. Thereafter, with pressure equalized, the shaft 24 of the flop valve is turned to move the same to its open position, as in Figures 1 and 2. The b ar B may then be moved downwardly as previously described and then turned to thread the lower end oi' the corporation cock into the tapped opening in the main Il. When the bar B is moved downwardly to position where the threads on the corporation cock come into engagement with the threads in the opening in the main. the cock can be threaded into the opening in the main by simply turning the bar B with a wrench. When the corporation cock is thusrigidly and finally attached, and because its valve is closed when it is inserted, the entire apparatus including the saddle I2 and the gasket |4 may be removed from the main. With the P- eration thus completed, the branch line is attached to the outer threads of the corporation cock in the usual manner.

Referring to Figures 4, 5 and 6, the chain yoke 48 is provided with diametrically opposed projections or lugs 90 and 90 each having arms |00 and |02 with an opening |04 between the same, said opening having fiat inner walls |00. As shown in Figure 5, the top faces of the arms are cut out to form concave cylindrical surfaces |00 and positioned across each pair of arms |02 there is a washer ||0 having a lower semi-cylindrical surface which engages the concave surfaces |08. The washer ||0 has a fiat top surface and a circular vertical opening I I2 therethrough.

As previously referred to, the apparatus is rigidly held on to the main by means of one or more straps or chains ||4 extending down under the main and having its ends secured to the chain yoke 46. At each end of the chain, there is a chain harp ||6 having an upper end which includes diametrically opposed fiat sides III and threaded areas |20 between said flat sides. The upper end of the chain harp is adapted to be inserted upwardly through the opening |044 between the arms of the chain yoke 4I and through the semi-cylindrical washer ||0. T'he chain is tightened to rigidly maintain the apparatus against the main by nuts |22 which are threaded onto the upper ends of the chainl yokes, which nuts bear against the flat tops of the senil-cylindrical washer ||0 to tighten the chain until there is sufiicient tension of the apparatus against the main to rigidly hold it and form pressure tight seals at the various packed unions. The firat inner sides |06 of the opening |04 between the arms of the chain yokes engage the fiat sides lll of the upper ends of the chain harps, so that as the nuts |22 are tightened, there is no tendency for the chain harps to turn or for the chain to twist. The fiat sides ||0 also assist in removing sand or mud from the inside of the nut |22.

The lower end of the chain harp is formed as shown in Figure 7, having a circular'opening |24 therethrough, large enough to pass entire links of the chain therethrough, and extending below this circular opening is an elongated narrow slot or recess |20, only slightly larger than the thickness of a chain link as shown in Figure 7.

When securing the apparatus to a main, the chain is lpulled taut through the chain harps ||6 on opposite sides of the apparatus, and one of the chain links is shifted so that its longest axis is disposed laterally across the slot |24 in the lower end of the chain harp. When the nuts ||2 are then tightened, this outside laterally disposedV link bears against the outer face of the chain harp on opposite sides of the opening |20 thus retaining the chain against movement through the chain harp. It will be understood thatsuiiicient tension is placed on the nuts |22 to securely hold the flop valve body "against tho saddle I2 and the saddle |2 against the main, so that packings 20 and |4 are compressed suiliciently to form a tight seal.

Figure 8 shows the top part of the cylinder 2l, with the :bonnet I0 attached thereto and with the lower end of the bar B extending into the outer fluid chamber, there being a holder 40' on the lower end of the bar. A tool or imple ment, such as a bit or corporation cock, is shown retained in the lower end of the holder, having the guide slot 'I4' as previously described engaging a guide lug 10 on the holder, there being a locking bolt 84' to retain the implement in place in the holder. In this modification, however, a different type of knock-out device is shown comprising a plunger |30-adapted to be hammered through an opening |32 leading from the upper end of the tool receiving hole in the bottom of the holder. The plunger |30 has a bevelled end surface |24 which engages against the bevelled end of the implement retained in the holder and dislodges the same after the retaining screw 04 is loosened. The plunger |30 has a relatively small slot |36 in its upper surface, and a pin |38 carried by the holder extends through this slot, so that the plunger cannot be entirely removed, or fall from, the holder.

In Figures 8 and 9, an arrangement of packing for rod B is shown with provision for tightening the same as the apparatus is used.- The circular cavity 34' in the bonnet is filled with packing, and extending through the side wall of the bonnet at the level of the packing, there is a threaded opening |40 (Figure 9). A packing tighening bolt |44 is tangentially threaded into the collar, entering the packing chamber. When the packing becomes worn, this bolt is threaded inwardly to tighten the packing, which is thus compressed entirely around the rod B.

Another form of rod packing means is shown in Figure 15, substantially identical with that of Figure 9,- except that a threaded collar |42 is used .between the threaded opening |40 and the threads of the tightening bolt |44. In bot-h Figures 9 and 15, the packing illustrated is of the hydraulic type, and the construction is such that it is accessible from the outside, but it does not change the height of the bonnet nor limit the depth of the tapping or other operations.

In prior art apparatus, it has been the custom to equip the bonnet 30 with special handles in order to thread the same over the upper end of the cylinder 28. In the present apparatus, we have provided means whereby the feed collar 5| may be utilized for this purpose, through its handles 52, to initially thread the bonnet onto the cylinder 28 and to remove and replace said bonnet between the performance of the vanous operations on a pressure main, as referred to above. As shown in Figure 10, at any desired position on the feed sleeve 5| between the handies 52, there is a radial opening |46 and in said opening a locking plunger |48 having a knurled head |50 is arranged for movement. This locking plunger has an inner end adapted to enter into a slot |52 in the outer wall of the .bonnet eitension 82, said slot being provided in the threaded area o f said extension. There is a ring |84 secured against the feed collar 8| at the outside of and around the opening |48 and a spring |88 in the opening |46 around Iplunger |88 is held by ring |84 and bears against a collar secured to the plunger |46 by a pin |82. spring |88 urges the plunger |48 inwardly so that its end may engage in the slot |82 in the bonnet extension. The head |88 of the plunger has a pair o! openings |88 therethrough, slightly larger than the heads of the screws |68 which secure ring |84 to the feed collar, and when said openims are aligned with the heads of the screws, the spring |88 forces the plunger inwardly until its end enters the slot |82 in the bonnet extension. .With the end of the plunger thus engaged in the slot, the handles 62 are turned to rotate the feed sleeve, this being done before the yoke I8 is engaged with the thrust collar 68 on the bar B, and the turning of these handles causes the bonnet to be threaded tightly onto the upper end of the cylinder 28. When the bonnet has been completely threaded on, the head |88 of the plunger |48 is pulled outwardly and then turned, so that the inner surfaces of the head |88 between the openings |80 ride upon the outer ends of the heads of the screws |86, and at this time, the plunger is completely withdrawn from the slot in the bonnet extension. Therefore, during the operation of moving the bar B inwardly, when cutting and tapping the opening in the main, the feed colla.;` can be rotated about the bonnet extension without rotating the latter, as previously described.

'I'he details of the bypass valve P are shown in Figures 11, 12 and 13. The tlop valve body i8, at its upper and outer side, is equipped with a machined surface |64 to receive a valve housing oi' the type shown in Figures 11 and 12. Passages |66 and |88 terminate at their outer ends in surface |64, passage |68 leading to the outer chamber of the housing of the apparatus above the flop valve seat while passage |60 leads to the inner fluid chamber of said housing below the flop valve seat. The bypass valve has a hollow housing which is secured to the surface |64 by bolts secured in threaded openings |12. One end of the interior of housing |10 comprises a chamber |14 which is constantly in communication with the passage |68 leading to the outer iluid chamber above the dop valve seat. The housing |18 has a conical longitudinal bore |16 leading from the chamber |14, and a transverse port |18 which leads from said bore to the surface |84 where it is aligned with the passage |68 leading to the iluid chamber of the apparatus below the ilop valve seat. I'here is a conical rotatable ground key valve member |80 positioned in the bore |16, and this valve member has a longitudinal passage |82 therein constantly in communication with the chamber |14, and a lateral valve port |84 which may be selectively aligned with the port |18 to establish communication between the passages |68 and |66, thus eilecting duid communication between the inner and outer chambers of the apparatus above and below the i'lop valve F. 'I'he bypass valve member |80 may be further turned to align with the relief port |88, which leads from the bore |18 of the valve housing to the open air. When the plug valve |88 is turned to align the port |84 with the relief port |88, the iiuid above the iiop valve may be relieved to the outside of the apparatus.

This operation of relieving the pressure is performed, as mentioned above, after any tool or implement is moved outwardly beyond the iiop valve and when said valve is then-closed, so that the pressure below the valve will keep it sealed. The valve plug |88 is also operated to relieve pressure from the interior oi' the apparatus at the completion of operations, and when it is intended to completely remove the apparatus from the main.

The valve plug is provided with a rotatable hand operated member or disc |88, to turn the plug. and a suitable stuiling box is provided around the plug to prevent escape from the valve housing.

In Figures 14, 16 and 17, a modiiication of the flop valve housing is shown which permits further shortening oi' the cylinder 28' which forms the tool inserting fluid chamber beyond the flop valve seat. 'I'he arrangement shown in these ngures is substantially the same as that previously illustrated except that the ilop valve housing I8 is of somewhat diierent design, as is the nop valve F' and its operating parts. The saddle |2 and pacldng |4 are positioned on the main i0 in the same manner as previously describedI and the modiiled Ilop valve housing I8 is secured onto the housing I2 by the chains ||4 in the manner described above. Furthermore, there is a bypass P', oi' any well known type, to control the passage of iiuid from below to above the flop valve, which operates in the same general manner as hereinbefore discussed. The ilop valve body has a globular enlargement forming a chamber 200 at one side of the flop valve seat and the outside of this chamber is covered by a removable globular cover plate 202, secured to the body by bolts, as shown. The chamber 200 is of such design and size, that the op valve may be completely housed therein, as shown in dotted lines in Figure 14. The flop valve F is provided with a circular sealing ring 204 to engage the valve seat, and may have a dished out portion or well 206, in order to permit shortening of the chamber above the valve, all as discussed above. The flop valve is carried on a substantially bifurcated right angular arm or lever 208 which is pivoted to an arm 2|0 by a pin 2|2, as shown in Figure 1'1. 'lhe arm 2|0 is inv turn rigidly secured to the squared portion of an operating shaft 2|4, said shaft extending to the outside of the housing where it carries an operating hand piece 2|6 to turn the valve between open and closed positions.

The op valve chamber 200 extends partially.

around the outside of the cylindrical guiding portion 220 of the flop valve body, and on opposite sides of said cylindrical portion 220, there' sumes the position shown in the full lines of` Figure 14. when the operating shaft zu is turned counter-clockwise, as viewed in Figure 14, the arm 2|0 moves with shaft 2|4 to its dotted line position, and the curved links 224 cause the ilop valve to be completely housed in the chamber 200 as indicated in dotted lines, substantially above or outwardly beyond the ilop valve seat. Thus, the length of the iiop valve body may be shortened from that shown in Figures l and 2, by housing the nop valve at the side of the body, rather than in aspace below the 'ilop valve seat. It will be apparent that the combination ot the use ot a nop valve with a dished out well and a housing which permits receiving ofthe valve at the side of the valve seat, permits substantial shortening of the ilop valve body, as well as oi' the cylinder forming the iluid chamber above the ilop lvalve seat.

It will be apparent that various changes may be made in the constructions shown herein without departinz from the invention. Features not claimed herein are claimed in divisional applications Serial Nos. 422,768, 422,769, 422,770. 422,771, 422,772, 422,773, 422.774, all entitled "Drilling apparatus" and all filed December 12, 19411.

We claim: Y

In a drilling machine, a barrel, a downwardly faced valve seat in said barrel demarking upper and lower chambers, means closing the upper end of the upper chamber, a boring bar rotatable and reciprocable in a bore provided inA said closing means, means limiting the upward movment of said bar, said upper chamber'being of such restricted height that when said bar is in its upper limit position a part carried thereby at its lower end will project below said seat, and a ilop valve swingable in said lower chamber and having a rim cooperative with said seat, said valve being dished within said rim to provide a well for the i'ree accommodation oi' the lower end of said part when the valve is closed.

FRANK H WALTER .'I. BoWAN.' 

